FISHERY OFFICER EXTENSION OFFICER (FO EO) -2020 Ball bearings replace sliding friction with rolling friction. Sliding friction occurs over a larger contact area between the axle and its housing. Ball bearings consist of spherical balls rolling between two races. The contact between the balls and the races is nearly point contact (in theory, or a very small ellipse in practice). This reduces the area experiencing friction and, crucially, replaces high sliding friction with much lower rolling friction.
Ball bearings are used in bicycles, cars, etc., because
Asked in UPSC IAS 2013 · Topic: Mechanics (Newton's Laws of Motion and their applications)
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Answer: C. the effective area of contact between the wheel and axle is reduced
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